Load straps are used to secure loads, primarily on flat bed trailer of tractor-trailer rigs. These straps readily adapt to any size load and securely hold such loads for long distances across interstate highways. If not used properly, loads can move about and possibly fall from the truck. If the cargo straps are tightened too tightly, they may damage the load or cause the strap to excessively wear and break. Much time is taken to ensure that the cargo straps are properly applied. This excessive time may cause many users to not properly apply the straps in an effort to save time. Also, after unloading a truck, all loose straps must be wound up on their reel, which, once again, takes a good deal of time. Accordingly, there is a need for a means by which load straps can be quickly and properly applied and rewound without risk of the dangers listed above. The development of the mechanism herein described fulfills this need.
The present mechanism comprises an apparatus designed to aid in the winding of cargo straps used on flat-bed trailers of tractor-trailer rigs comprising a metal cylinder with an internal helical spring. A first end of the cylinder is a closed outer spring case while a second end is a winching gear and locking assembly, both of which are mounted to a standard cargo strap winch system commonly found on conventional flat bed tractor trailers. A similar arrangement is used on all cargo winch systems on a truck. To use the invention, the user simply pulls out enough strap to anchor on an opposite side of the truck and over a carried load. The strap is then tightened and cinched down in a conventional manner. When unloaded, a lever is simply released, and the entire cargo strap is quickly retracted back onto a winch shaft. This not only represents a huge time savings for the truck driver, but also protects the stored cargo strap from damage.
Several attempts have been made in the past to secure cargo to vehicles particularly using strap and tie-down mechanisms. U.S. Pat. No. 4,011,974, issued in the name of Scarola, describes an apparatus for securing cargo to a vehicle comprising an elongated flexible member having a fastening mechanism attached to one (1) end for securing said end to said vehicle. However, unlike the present mechanism, the Scarola cargo strap is intended for use with a passenger vehicle and utilizes a mechanical screw to tighten the flexible strapping member.
U.S. Pat. No. 6,059,499, issued in the name of Bird, discloses a retractable strap assembly comprising a spool having wound strapping member and a spring entirely within a mountable housing assembly. However, unlike the present mechanism, the Bird retractable cargo securement strap comprises elongated arms and pivoting members to operate the retractable spool assembly does not provide a mechanism to ratchet down the cargo strap into a tight and secure position.
Other known prior art cargo securement straps and spring mechanisms include U.S. Pat. Nos. 4,860,408, 4,216,922, and 4,564,308.
The prior art appears to disclose various attempts at cargo securement using strapping members. However, none of the prior art particularly describes an apparatus comprising a cargo strap winching shaft, a winch assembly for tightening said strap, and a spring assembly for automatically retracting said strap after use. Accordingly, there exists a need for a retractable cargo strap that operates without the disadvantages as described above.